Originally Posted by jfw432
If you haven't fixed this yet, I have another option for you. You could drill a 1/4" or 5/16" hole in both the knob and the shaft, tap both for a bolt, cut the head off a 1.5"-2" bolt, then thread half the bolt into the knob, and finally screw the knob and other half of the bolt onto the shaft. Use loctite on both ends and it'll work for many years to come.
I thought about the same thing but I think he's got a new knob he wants to install. I guess you could try to bore and tap the handle with the same thread size as the new knob and use the same technique.